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From your photos, your soldering looks fine. The fried transistor could be causing that continuity now.? Since you have ordered a new one, you could just remove the current one and see if the short

Hi all I have just built and finished my first QMX+ and it worked first time well impressed. Just one question on the power output which I am measuring into a dummy load. On 160m I am getting 7.2w,

Hi With all that gain, you can use it for HackRF kind of miliWatt SDR transceivers. Even with U4B baloon Tracker 73 DE muhsin TA1MHS > > >

Hi Sergey My QMX works great with 1_01_003 firmware. I've calibrated it and SSB Great! Few problems: In version 1_00_003 the power meter reads peaks. Not averages. Then there is also a hold time. It

Stan, Thank you very much for your detailed reply. After trying some of your triage steps, I am observing that the GND, +12V, and VCC all exhibit continuity with each other on the compromised SMP

I have rev 2. When I plug in the power it still shows as 12 on the board. It only draws power when I press the power button. [email protected]> wrote:

For that TVS diode (right alongside the power connector), the forward 0.6V drop is not the critical thing - it is the reverse breakdown, and I'm not sure if the 'diode test' function of a multimeter

The MOSFET would blow from over-current, not over-voltage.? And high current will happen if +5V is somewhere shorted to ground, or Q108 is turned on all the time, which causes zener D108, which is

Austin, If your screen lighted up and Q108 blew without you pressing the power-on button, it means you have one or more shorts going on.? That display tab can cause shorts in the power supply, but

I just checked the diode and it seems to be fine with a 0.6v drop. [email protected]> wrote:

...the Images: https://github.com/dl4pj/qmxfiltersim/blob/main/images/buggyplot.png https://github.com/dl4pj/qmxfiltersim/blob/main/images/bypass20m.png

Hello, I am doing some experiments with the qmx filter sections. E.g. I bridged the BPF and LPF section by a cap. I wanted to test, how flat the sweeps are without any filter. The results are good

Very nice quality, Chris.? Thanks for posting!

If you just ordered it, it's a Version? 3.? ?Hans said at the start that he would not ship 3 until the stock of older versions is empty.? I ordered? weeks ago and it was a 3. Printing in color

https://www.allaboutcircuits.com/technical-articles/introduction-to-the-feed-forward-linearization-of-rf-power-amplifiers/?user_mcid=3b7c12b4be

https://youtu.be/fImxAz-MeQ4

Hello, I recently just fished putting my QMX Rev 4 kit together with the windings necessary for 12v input. As I was going along I verified I all continuity checks as instructed and verified no pads

I tested the quality of the SSB transmission today. A standard electret microphone with a mic gain of 55 and a compressor of 3-5 and at the end. The receiver was an FT-817. 73

Hi Norm > I know about the wattage differences compared with S-meter readings, etc., The probability is certainly non-zero. But I don't have any concrete plans for a 10W QMX+ at the moment. Bear in

I don't know if any of you has noticed anything similar: while performing the SSB calibration on a band-by-band basis (using the "O" option) I noticed that at the end of the USB/LSB IMD Optimization